package demo1;

public class StringDemo2 {

	public static void main(String[] args) {
		/*String name = "张";
		name+="三";
		//System.out.println(name);
		String a = "亮当时发生地方adf";
		char c = a.charAt(0);
		//int i = a.codePointAt(0);
		for (int i = 0; i < a.length(); i++) {
			System.out.print(a.charAt(i)+" ");
		}
		
		String str = "adlkjhsdfgadfga";
		System.out.println(str.indexOf('d',4));
		String name = "不开心活好每一天,不可能";
		String s = name.substring(1,8);
		System.out.println(s);
		*/
		String str = "I m a Boy";
		String Case = str.toUpperCase(); //大写
		System.out.println(Case);
		System.out.println(Case.toLowerCase()); //小写
	}
}
